only sound which works are the XP sounds... no MP3s ect

Hey everyone, I was wondering if someone could provide a possilbe reason that I can not hear any sounds except for the XP exclamation sounds and shutdown. I have reinstalled my soundcard driver (Hercules Grandfortissmo Surround II). I need my sound back! Any help would be greatly apreciated

its not the programs... the problem lies in the fact that no sound will work for anything besides the windows startup and shutdown sound. Any program (beit AIM or Windows Media Player) do not eminate any sound.